A 58-year-old woman is evaluated in the surgical clinic after routine laboratory testing reveals a serum calcium level of 11.4 mg/dL (normal: 8.4-10.2 mg/dL). She has a history of nephrolithiasis and complains of generalized fatigue. Arrange the following steps in the most appropriate chronological sequence for the evaluation and definitive surgical management of this patient's condition.
- 1Measurement of serum intact parathyroid hormone (PTH) concentration
- 2Measurement of 24-hour urinary calcium excretion
- 3Parathyroid localization using a sestamibi scan and neck ultrasound
- 4Minimally invasive parathyroidectomy
Answer
The correct sequence is: Measurement of intact PTH -> Measurement of 24-hour urinary calcium -> Parathyroid localization studies -> Parathyroidectomy.
The correct sequence ensures that primary hyperparathyroidism is accurately diagnosed (high calcium and high PTH), distinguished from familial hypocalciuric hypercalcemia (via 24-hour urine calcium), anatomically localized, and definitively treated with surgery.
Step-by-Step Solution
Key Concept
The standard diagnostic and surgical algorithm for primary hyperparathyroidism requires biochemical confirmation and ruling out FHH before anatomical localization and surgical resection.